Extrusion of films of vinylidene fluoride polymers
US4481158A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1982 |
| Grant date | Nov 6, 1984 |
| Priority date | — |
| Expiry date | Nov 16, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2327/02
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The film (11) extruded from a vinylidene fluoride polymer is subjected to a stretching of at least 200% while still in the molten state, and then cooled rapidly to a temperature below 50.degree. C. The equipment comprises, in series, an extruding device (1) (2), a cooling device consisting of a thermostatically controlled liquid bath (6), the level of which is located at a distance of 10 to 300 mm from the extruding device, and a device (8) (9) for stretching the extruded film by at least 200% in its part located between the extruding device and the cooling device. The film obtained is suitable for manufacturing piezoelectric films.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.